Transcript for Officer on trial for the shooting of a 6-year-old boy in Louisiana

Back now with an officer on trial for the shooting death of a 6-year-old boy in Louisiana. The jury today seeing the bodycam video. Here's ABC's Steve osunsami. Reporter: Louisiana's top cop has called this deadly police shooting of an autistic child the most disturbing thing he's ever seen. It disturbed me as a father. Reporter: And in opening statements today, in the trial against one of the officers accused, prosecutors piled on, telling jurors that deputy marshal Derrick Stafford, seen here, was facing no real danger when they say he and officer Norris greenhouse fired 18 bullets into this SUV, after a chase through the streets of marksville, Louisiana. Several of those bullets struck and killed 6-year-old Jeremy Mardis, still strapped in the front seat. Here's the moment, caught on video, when Stafford realizes a child was inside. I never saw a kid in the car man. Yeah. The kid is -- I never saw a kid in the car, bro. I was just keep telling him to stop. Reporter: The jurors wiped away tears. You see the boy's father who was driving the car, had his hands up when the officers started firing. You see that right here. He was unarmed, was seriously wounded, and prosecutors say he'll testify, explaining that he was running because he was afraid he would lose custody of his son. Stafford is pleading not guilty, and his lawyers say the boy's father is the one who's at fault for running B. Some? Steve osunsami, thanks so much.

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The jury foreman in the state murder trial of former North Charleston, South Carolina, police officer Michael Slager described the climate in the jury room as "passionate, emotional" and sometimes "heated" before a mistrial was eventually declared.

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